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Modulation of Renin‐Angiotensin System May Slow Conversion from Mild Cognitive Impairment to Alzheimer's Disease 下载免费PDF全文
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Kyle J. Chambers Ashton E. Lehmann Aaron Remenschneider Matthew Dedmon Josh Meier Stacey T. Gray Derrick T. Lin 《Skull base》2015,76(2):94-100
Objective To determine trends in sinonasal undifferentiated carcinoma (SNUC) survival patterns in the United States.
Design Retrospective review of national database.
Participants All cases of SNUC in the National Cancer Institute''s Surveillance Epidemiology and End Results program from 1973 to 2010 were examined.
Main Outcome Measures Age-adjusted incidence and survival rates were calculated and stratified by demographic information and treatment modality. Cohort analysis was performed to analyze survival patterns over time.
Results A total of 318 SNUC cases were identified. Age-adjusted incidence rate (IR) was 0.02 per 100,000. Incidence was greater in males (IR: 0.03) than females (IR: 0.01; p = 0.03). Overall 5- and 10-year relative survival rate was 34.9% and 31.3%, respectively. Overall median survival was 22.1 months. Median survival following surgery combined with radiation was 41.9 months. Five-year relative survival rate following surgery, radiation, or surgery combined with radiation was 38.7%, 36.0%, and 39.1%, respectively. Median survival from 1973–1986 and 1987–2010 was 14.5 and 23.5 months, respectively.
Conclusions This study provides new data regarding survival patterns of SNUC in the United States, confirming survival benefit with surgery and radiation as well as identifying a trend toward improved survival in recent decades. 相似文献
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Philip J. Swaney Hunter B. Gilbert Robert J. Webster III Paul T. Russell III Kyle D. Weaver 《Skull base》2015,76(2):145-149
Objectives The purpose of this study is to experimentally evaluate the use of concentric tube continuum robots in endonasal skull base tumor removal. This new type of surgical robot offers many advantages over existing straight and rigid surgical tools including added dexterity, the ability to scale movements, and the ability to rotate the end effector while leaving the robot fixed in space. In this study, a concentric tube continuum robot was used to remove simulated pituitary tumors from a skull phantom.
Design The robot was teleoperated by experienced skull base surgeons to remove a phantom pituitary tumor within a skull. Percentage resection was measured by weight. Resection duration was timed.
Setting Academic research laboratory.
Main Outcome Measures Percentage removal of tumor material and procedure duration.
Results Average removal percentage of 79.8 ± 5.9% and average time to complete procedure of 12.5 ± 4.1 minutes (n = 20).
Conclusions The robotic system presented here for use in endonasal skull base surgery shows promise in improving the dexterity, tool motion, and end effector capabilities currently available with straight and rigid tools while remaining an effective tool for resecting the tumor. 相似文献
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Christopher A. Rice Beatrice L. Colon Mehmet Alp Hakan G?ker David W. Boykin Dennis E. Kyle 《Antimicrobial agents and chemotherapy》2015,59(4):2037-2044
Naegleria fowleri is a pathogenic free-living amoeba (FLA) that causes an acute fatal disease known as primary amoebic meningoencephalitis (PAM). The major problem for infections with any pathogenic FLA is a lack of effective therapeutics, since PAM has a case mortality rate approaching 99%. Clearly, new drugs that are potent and have rapid onset of action are needed to enhance the treatment regimens for PAM. Diamidines have demonstrated potency against multiple pathogens, including FLA, and are known to cross the blood-brain barrier to cure other protozoan diseases of the central nervous system. Therefore, amidino derivatives serve as an important chemotype for discovery of new drugs. In this study, we validated two new in vitro assays suitable for medium- or high-throughput drug discovery and used these for N. fowleri. We next screened over 150 amidino derivatives of multiple structural classes and identified two hit series with nM potency that are suitable for further lead optimization as new drugs for this neglected disease. These include both mono- and diamidino derivatives, with the most potent compound (DB173) having a 50% inhibitory concentration (IC50) of 177 nM. Similarly, we identified 10 additional analogues with IC50s of <1 μM, with many of these having reasonable selectivity indices. The most potent hits were >500 times more potent than pentamidine. In summary, the mono- and diamidino derivatives offer potential for lead optimization to develop new drugs to treat central nervous system infections with N. fowleri. 相似文献
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Kerri A Simo David J Niemeyer Erin M Hanna Jacob H Swet Kyle J Thompson David Sindram David A Iannitti Ashley L Eheim Eugene Sokolov Valentina Zuckerman Iain H McKillop 《HPB : the official journal of the International Hepato Pancreato Biliary Association》2014,16(6):534-542
Background
Hepatic regeneration requires coordinated signal transduction for efficient restoration of functional liver mass. This study sought to determine changes in lysophosphatidic acid (LPA) and LPA receptor (LPAR) 1–6 expression in regenerating liver following two-thirds partial hepatectomy (PHx).Methods
Liver tissue and blood were collected from male C57BL/6 mice following PHx. Circulating LPA was measured by enzyme-linked immunosorbent assay (ELISA) and hepatic LPAR mRNA and protein expression were determined.Results
Circulating LPA increased 72 h after PHx and remained significantly elevated for up to 7 days post-PHx. Analysis of LPAR expression after PHx demonstrated significant increases in LPAR1, LPAR3 and LPAR6 mRNA and protein in a time-dependent manner for up to 7 days post-PHx. Conversely, LPAR2, LPAR4 and LPAR5 mRNA were barely detected in normal liver and did not significantly change after PHx. Changes in LPAR1 expression were confined to non-parenchymal cells following PHx.Conclusions
Liver regeneration following PHx is associated with significant changes in circulating LPA and hepatic LPAR1, LPAR3 and LPAR6 expression in a time- and cell-dependent manner. Furthermore, changes in LPA–LPAR post-PHx occur after the first round of hepatocyte division is complete. 相似文献99.
100.
Temporal patterns of gene expression in developing maize endosperm identified through transcriptome sequencing 总被引:1,自引:0,他引:1
Guosheng Li Dongfang Wang Ruolin Yang Kyle Logan Hao Chen Shanshan Zhang Megan I. Skaggs Alan Lloyd William J. Burnett John D. Laurie Brenda G. Hunter Joanne M. Dannenhoffer Brian A. Larkins Gary N. Drews Xiangfeng Wang Ramin Yadegari 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(21):7582-7587